Question

A full journal bearing has a journal with a diameter of 2.000 in and a unilateral tolerance of -0.0012 in. The bushing has a bore with a diameter of 2.0024 in and a unilateral tolerance of 0.002 in. The bushing is 1 in long and supports a load of 600 lbf at a speed of 800 rev/min. Find the minimum film thickness, maximum film pressure, coefficient of friction and total lubricant flow if the average film temperature is 130°F and SAE 40 lubricant is used. The tightest assembly is to be analyzed.

Answer 1

Soyly Given that, 2.000 in = -0.0012 in 2.0024 in 0.ool in - I A Diame for of shoff (d) = unila ferol tolerance of shaft Diameter of bushing hore (6) - unica forar flerance of busting bore length of bushing here 12- Bushing hoad IN)= 600 chf Considering minimum homin duin Comin = radius to clearance ratio fearance assembly, Comin 0.0012 en 2.000 2.0ory 2 2 8.33.33 d ze 2x 0.0012 600 - 300 psi W pressure 1x2 unit had Revolution 13.33 sps second (N) por SAE uo wbricans, riscosity at 130°F 8 t=1474.4 of SAE UO 1.210 10 reyn 1474.4 Mo exp expl } 1.21xrors T4 195 *** xepp? 130f95 = M = So 485 x 10-6 Summer field nurser (s) 8.4858 10 13:33) (833.33)2 -0.2618 s- 300 - ho = exo.2 = 0.00124 0.2 Nove hot -0.2 ho = 0.00024 0.2 6.2618 - 0.36 & Phar Pomax 300 F233:33 psi p 0.36 0.36 = Prax =

Flu for 6 6 3) f = 6x9 = 0.0072 833.33 0.2618 Š = 4.98 Real RonL a = 449 4.98 (RanL) - 4.98 (13.33 x 22 x 0.0012 x1) - o.or966